Floor and upholstery cleaning machines include a vacuum tube that is connected to a cleaning head at one end and to a vacuum source at the other end. A nozzle, provided in or near the cleaning head, sprays a cleaning solution on a surface to be cleaned. The cleaning solution and dirt particles are then extracted and sucked into the cleaning head and the vacuum tube by the action of vacuum.
An operator moves the cleaning head along the surface to be cleaned by holding a handle coupled to the cleaning head with one hand while actuating, with the other hand, a lever also coupled to the vacuum tube that opens or closes a valve controlling the flow of the cleaning solution.
Examples of these types of cleaning machines are disclosed in U.S. Pat. No. 5,483,726 to Blase et al.; U.S. Pat. No. 5,542,147 to Merten; U.S. Pat. No. 5,891,198 to Pearlstein; and U.S. Pat. No. 6,263,539 to Baig.
FIG. 1 illustrates use of a floor cleaning machine according to the prior art. Vacuum tube 10 is held by the operator with both hands by gripping handle 12 provided on vacuum tube 10 with the left hand while at the same time holding the vacuum tube at a different point with the right hand. The flow of the cleaning solution sprayed on the surface to be cleaned is controlled by having the operator actuate control lever 14 with the right hand, opening or closing valve 16 which is disposed under vacuum tube 10.
Those hand positions are not ergonomic and after some time the operator becomes fatigued from holding and moving vacuum tube 10 with his arms spread apart while at the same time operating control lever 14.
Moreover, the cleaning solution is often hot and while the hand holding handle 12 is protected from the heat of the cleaning solution (provided that handle 12 is made of an insulating material), the other hand becomes inevitably exposed to heat after some time due to heat either transmitted or radiated from solution valve 16 to control lever 14. In addition, the disposition of the operator's hands in machines of the prior art is such that the hand which actuates control lever 14 may slide along tube 10 and come in contact with solution valve 16 and, therefore, become exposed to heat.